mNeonGreen

mNeonGreen is a monomeric green fluorescent protein used as a fluorescent reporter in live-cell imaging. It was engineered to be significantly brighter than enhanced GFP (EGFP) and to mature rapidly in mammalian cells. The protein is derived from a natural fluorescent protein found in reef coral species and has been optimized for high expression and stability across diverse organisms. As a monomer, it minimizes interference with the fused protein’s localization and function, and it exhibits strong photostability and a wide pH tolerance near physiological conditions.

Spectral properties and imaging uses: mNeonGreen has an excitation peak around 506 nm and an emission peak around 517 nm, placing it in the green channel of most fluorescence microscopes. It is commonly used as a bright green donor in fluorescent protein fusions and as a reporter in live-cell assays; it can also serve as a donor in FRET pairs with red- or far-red fluorescent proteins. It is broadly compatible with standard imaging setups and is frequently codon-optimized for mammalian expression.

Applications and availability: It is widely used in bacteria, yeast, plants, and mammalian cells, in fusion constructs to monitor protein localization, trafficking, and interactions. Plasmids encoding mNeonGreen are available through major repositories such as Addgene. While it offers brighter signals than GFP in many contexts, researchers should consider spectral bleed-through in multi-color experiments and its performance can vary with illumination, temperature, and cellular environment.